C#

BillWoodruff wrote:

Thanks for your very thoughtful reply

BillWoodruff wrote:

Aren't all delegates inherently multi-cast

BillWoodruff wrote:

It's interesting to me that some third-party controls I use that expose Events
really do not provide a practically useful object in the Events 'object sender
parameter.

Bastard Programmer from Hell
If you can't read my code, try converting it here[^]

Eddy Vluggen wrote:

there's always a sender - it's an object, so there's no excuse for passing "null" there.

Event Design[^]

Do not pass null as the sender parameter when raising a non-static event.
On static events, the sender parameter should be null.

C# Event Implementation Fundamentals, Best Practices and Conventions[^]

Static events should pass null as the value of sender

private List<MyObject> MyList;
void Main()
{
   var items1 = Get(x => x.MyInt == 1);
   var items2 = Get(x => x.MyBool == false);
   var items3 = Get(x => x.MyString == "XXX");
   var items4 = Get(x => x.MyBool == false && x.MyString == "XXX");
}

public IEnumerable<MyObject> Get(Func<MyObject, bool> filter) {
	if(MyList == null) MyList = new List<MyObject>();
	if(MyList.Count==0) {
		MyList.Add(new MyObject { MyInt = 1, MyBool = true, MyString = "XXX" });
		MyList.Add(new MyObject { MyInt = 2, MyBool = false, MyString = "XXX" });
		MyList.Add(new MyObject { MyInt = 3, MyBool = false, MyString = "YYY" });
	}
	return MyList.Where(filter);
}

// a data object contained in the list
public class MyObject {
   public int MyInt { get; set; }
   public bool MyBool { get; set; }
   public string MyString { get; set; }
}

BillWoodruff wrote:

But, I guess if I were part of a team, on a large, complex, project, implementing Events in the usual way with custom EventArgs would probably pay off in the long-run. Possibly contributing to code consistency and maintainability ? Flexibility ?

BillWoodruff wrote:

However, I will point out that the implementation of a revised EventArgs class, and using it, will also require changes to each place in your code that raises the Event: to initialize the new parameters.

class Program {
    static void Main(string[] args) {
        var x = new MySender();
        x.MyEvent += MyHandler;
    }
    
    private static void MyHandler(object sender, EventArgs eventArgs) {
        // Do Stuff
    }
}
public class MySender {
    public event EventHandler MyEvent;    
    // Event Invocators etc.
}

class Program {
    static void Main(string[] args) {
        var x = new MySender();
        x.MyEvent += MyHandler;
    }
    
    private static void MyHandler(object sender, EventArgs eventArgs) {
        // Do Stuff
    }
}
public class MySender {
    public event EventHandler<CustomArgs> MyEvent;    
    // Event Invocators etc.
}
public class CustomArgs : EventArgs {
    public int MyInt { get; set; }
}

class Program {
    static void Main(string[] args) {
        var x = new MySender();
        x.MyEvent += MyHandler;
    }
    
    private static void MyHandler(object sender, CustomArgs eventArgs) {
        // Do Stuff
        var x = eventArgs.MyInt;
    }
}
public class MySender {
    public event EventHandler<CustomArgs> MyEvent;    
    // Event Invocators etc.
}
public class CustomArgs : EventArgs {
    public int MyInt { get; set; }
}

Nitin K wrote:

Can we apply transaction rollback

Bastard Programmer from Hell
If you can't read my code, try converting it here[^]

Member 11117384 wrote:

can anyone solve my issue

coolsuhail wrote:

and the message show path not found